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AC6 charging AAs in TX?

AC6 charging AAs in TX?

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Old 10-09-2012, 09:53 AM
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Default AC6 charging AAs in TX?

I just bought some 2200 mAh rechargeable NiMH AA's from HobbyPartz for my Team Associated XP3-SS Tx. My Tx has a charging jack and I made a cable for it from the extra cables I had with my Thunder AC6 charger. I was sure to check the polarity on the cable when I made it with the Tx jack which shows a diagram of the polarity.

Here are some question I have:
1. At what rate should I charge these batteries?
2. How long...or should I check my AC6 charger for some voltage indication? (I read the manual, but it wasn't very clear, or I just didn't get it)
3. Would these be charged in series or parallel considering they will be charged in the Tx?
4. My Tx has battery indicator lights, green for good, yellow for mid, red for low battery and low+beeping for really low battery. Is it OK to charge them up when they are at yellow, or is it not good to partially charge NiMH batteries or should I wait until they get as low as possible?
5. I don't want to damage the batteries with fast charging or heat issues, but I don't want them to take forever either, what are my options?

TIA
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Old 10-09-2012, 12:49 PM
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1. I like 0.5 amps, but watch cell temps. Some go higher, say 1 amp, but generally they get warmer than I care for, especially in a closed space like in the transmitter with limited cooling airflow. Probably need to stay above 0.2A or so or risk not having the voltage delta peak charge termination work correctly, the charger wonít shut off correctly.

2. The charger should shut off automatically if set on nimh mode. The charger should shut off after detecting a voltage peak as it then drops off. The exact voltage will vary due to a variety of factors. At 0.5A up to perhaps 5 hours or so would be required from fully discharged.

3. Series.

4. Generally OK to charge them whenever. Ideally get a full discharge in every 10 cycles or so.

5. If they donít get overly warm (<110F?) try turning the amps up some. But if you charge them occasionally you wonít need a full charge either, so that helps.


Off subject suggestion, next time you buy rechargeable AAs look for the Low Self Discharge types, they work great in transmitters. Also labeled Ready to Use.

Last edited by Dave H; 10-12-2012 at 04:07 PM. Reason: Ready to Use not ready to run
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Old 10-09-2012, 04:34 PM
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Thank you.

These AAs have a different term for the Low Self Discharge, EMB and they say Ready to Use on the pack, on the back they have a graph illustrating Energy Retention Over Storage Period indicating that they only loose 15% charge over 12 months...maybe this China company wanted to compete with LSD and came up with it's own term...we'll see, but they got great reviews over at HobbyPartz.

BTW, do you know how I can run a discharge on my AC6 charger? I guess there would be a discharge setting, but does again the charger turn itself off and is there a discharge rate for discharging?
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Old 10-12-2012, 04:09 PM
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Ah, sounds like you have the good kind already, excellent. I corrected my post, yes ready to use, not run, must have had a brain dump.

Discharging unmatched cells in a pack can be an issue. But generally a similar current, 0.5A give or take, down to 0.9 volts per cell. Again avoid excessive heat. The risk is having some cells drop to zero or get reversed while others are still going, they can be damaged. Perhaps not likely with new cells from the same batch, but something to be aware of.

If you want to maximize the batteries performance and life, probably only worth it if you use them in lots of other devices, the best way is to do them individually.

This is generally considered the best. Has cycling, break in, refresh, etc modes, and even provides data. Folks who have splurged really seem to like them.

These guys have a variety of less expensive alternatives. Look for the smart models with delta V cutoff and independent channels & discharge function in the features column. I’m sure there are others too.
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Old 10-12-2012, 10:22 PM
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The EMB NiMH Cells from Hobbypartz are actually pretty good. I've got them in all my transmitters. They are Low Self-Discharge cells.

I charge my GT3B and two Traxxas Transmitters (Modified for Charging Jacks) at 0.8A without temp issues.
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